It is known in the prior art to combine an air driven power supply, such as a fluidic generator, with a projectile fuze. See, for example, U.S. Pat. Nos. 3,568,704; 3,772,541; and 3,971,321. When such a device is positioned in the fuze ogive of a projectile or missile, ram air enters through an air inlet means and passes through a nozzle. The nozzle, which contains a nozzle-centerbody, directs the air to a resonant cavity. The air entering the resonant cavity produces acoustical vibrations. The acoustical vibrations cause a daphragm, which is mounted in the resonant cavity, to oscillate. The oscillating diaphragm drives a metallic reed which is set in a permanent magnetic field. This induces a current in a coil, which is used to power the fuze electronics.
When an air driven generator, of the type just described, is used aboard a projectile, it can experience velocities of 3000 feet per second or higher. These high flight velocities cause a large mass flow to enter the air inlet of the generator. The large mass flows cause the diaphragm to experience large displacements. When the displacement of the diaphragm is large enough, a condition is reached where the metallic reed bangs against the pole pieces of the magnetic device. This banging causes noise in the electrical output and, more importantly, fatigues the reed, which will eventually break causing a power loss in the fuze electrical system.
Prior attempts to regulate the flow of air into the fuze comprise mainly movable valves which responded to such variables as acceleration, air pressure, etc. Such devices met with limited success as they were highly sensitive and required delicate calibrations. Also, the high magnitude of mechanical forces experienced by the devices, as well as aerodynamic heating, resulted in many failures and a low degree of dependability.
One method to regulate the air flow into the fuze is to provide an air deflector in the air inlet means of a fuze ogive. See U.S. Pat. No. 4,362,106. There, the deflector comprises a stationary deflecting surface configured so as to substantially reduce the amount of air entering the ogive during high velocity flight, while not substantially reducing the air inflow during low velocity flight.
It is an object of this invention to provide a device which produces control jets to deflect portions of the incoming air flow away from the resonator.
It is a further object of this invention to provide a device which will deflect major portions of the incoming air flow during high velocity flight.
It is also an object to provide such a device which would not substantially affect the inflow of the air to the resonator during low velocity flight period.
It is a further object of this invention to use a plurality of air passageways in the nozzle-centerbody to produce the control jets.
It is a further object of this invention to provide a device for producing control jets which is simple, inexpensive, and has no moving parts requiring calibration.
It is an additional object of the invention to provide such a device which has infinite shelf life, not experiencing any degree of deterioration in storage.